1. Field of the Invention
The invention relates generally to the field of photography, and in particular to a torque transmission clutch for a film spool preferably used in a film cassette.
2. Description of the Prior Art
New film cassettes have been devised, such as disclosed in commonly assigned U.S. Pat. No. 5,151,730, issued Sep. 29, 1992, which, unlike conventional 35 mm film cassettes, will advance at least the film leader of a filmstrip wound on a film spool inside the cassette out of the cassette responsive to rotation of the film spool in a film unwinding direction.
3. Problem to be Solved by the Invention
When one of the new film cassettes is loaded into a camera, a rotational driver is received in a coaxial opening in the spool core of the film spool to rotate the film spool in a film unwinding direction in order to advance the film leader from the cassette for picture-taking. If, however, the film leader initially becomes jammed in the camera, it is necessary to discontinue rotation of the film spool in the film unwinding direction before the filmstrip can be damaged and to rotate the film spool in a film winding direction to return the film leader to the film cassette.